Maximum Axle Load Weight

It is common to see weigh stations along interstates for the purpose of weighing trucks to make sure that they are within the limitations. There are a few reasons that trucks have weight limitations on roads and need to be properly weighed. The main reason is safety. Roads can only handle a certain amount of weight, especially in weaker spots such as bridges and overpasses; therefore, no vehicle can be over the weight limit of the weakest point on the road. Additionally, cargo that is too heavy can be dangerous to both the driver and other vehicles on the road. A truck that is carrying too much weight can make it difficult to brake and maneuver, posing a danger when trying to slow down or go down a hill. The other two reasons for weighing trucks are taxes and profitability. Carriers pay taxes for the amount of stress put on the roads, and the weight of the trucks is used to calculate the taxes owed. As for profitability, many goods are valued based on their weight; therefore, weight is important in ensuring fair trade and increasing profits. There are three different weights for trucks regulated by each state. The first is the maximum gross vehicle weight is the weight of the vehicle specified by the manufacturer including its chassis, body, engine, engine fluids, accessories, drivers, passengers and cargo. The maximum single axle weight is the amount of weight allowed on any one axle. The maximum tandem axle weight is the weight allowed on any tandem axle. Trucks can be weighed by using wheel-weighers, concrete decks, portable truck scales, digital scales and more. Trucks that are found to be overweight at a weigh stations can face several consequences including paying fines up to $65 per pound overweight and, in some states, arresting the driver. It is important that each truck is weighed before departing on its route to avoid these repercussions. The federal vehicle weight limits are 80,000 pounds gross vehicle weight, 20,000 pounds on a single axle, and 34,000 pounds on a tandem axle group. States, however, often have different limits. The table below has each state’s maximum allowed weight for gross vehicle weight, single axle weight, and tandem axle weight. As core stakeholders of the transportation industry, it’s not uncommon for shippers, like you, to have questions about transportation’s many facets. The answers to these, and questions like these, can sometimes feel hidden in the fast-paced world of transportation and leave you feeling undervalued, unseen and forgotten. Recently, your questions regarding the legal axle weight limits for freight transported on tandem-axle and tridem-axle trailers have been unanswered – leaving you without direction once more. With something as important as the health of your company’s supply chain on the line, you deserve much better from the transportation businesses that keep America’s industries afloat. Here at Anderson Trucking Service (ATS), we have an extensive fleet of semi-trailers and a deep knowledge of the rules and regulations that accompany running them. While the total amount of axle weight your shipment will be allowed varies both by time of year and across state lines, an understanding of these things will do you well in the future. In this article, you’ll find an in-depth overview of:. At its conclusion, this article will remove a lot of confusion from this process and leave you far better suited to plan your loads according to legal axle weight limits. According to the federal government’s gross vehicle weight guidelines — without permitting — semi-trucks and the loaded trailer behind them can weigh no more than 80,000 pounds collectively. This 80,000-pound limit governs the movement of all multi-piece freight shipments — like loads of steel I-beams — which can be evenly distributed, yet still pose a risk of equipment damage and safety concerns. The percentage of these 80,000 pounds — which includes the overall curb weight of each semi-tractor — that’s dedicated to hauling your freight will change based on the weight of your truck and trailer combo when “empty.”. Dry van trailers, for example, weigh more than flatbed and step-deck trailers. Though this added heft can be attributed to the fiber-glass encasement, keeping van freight protected from the elements in transit, it also means that dry van trailers allow less load weight than other trailer types. Beyond solely dry vans, the construction of many trailer types will also vary, decreasing or increasing their overall weight accordingly. For your reference, here are some general freight-weight thresholds for the three most common, tandem-axle trailer types:. 53-foot refrigerated trailers can usually haul between 43,000 to 45,000 pounds. 53-foot flatbed trailers can typically haul between 45,000-48,000 pounds. 53-foot dry van trailers can typically haul between 43,000-46,000 pounds. With these ranges accounted for, the remaining 32,000 (or so) legally-alloted pounds must be dedicated to the tractor pulling every load. But how much weight — which must be properly distributed — should a semi truck’s axles (one steer and two drive) respectively bear? The steer axles — located at the front of a semi-truck — typically hoist 12,000 to 15,000 pounds (or 6,000 to 7,5000 pounds on each tire). This total, however, may fluctuate slightly depending on the make and model of the vehicle in question and the overall weight distribution of the load in question. To land within the federally-allowed 80,000 total pounds of gross vehicle weight, the two drive axles of a class-8 semi-tractor typically hold no more than 34,000 pounds. Broken down further, this 34,000 pounds is distributed at 17,000 per axle and 4,250 pounds for every tire. For single-piece freight shipments that exceed the legally allotted 80,000 pounds of gross vehicle weight, overweight permitting must be acquired from each state, city and/or township it’s traveling through. It’s at this point that legal axle weight limits also come into play. States define the thresholds for single, tandem and tridem-axle freight movement on an individual basis. Let’s talk about them. According to federal rules and regulations, the maximum amount of cargo weight for single-axle transportation equipment is 20,000 to 25,000 pounds. This limit applies to one-axle trailers, boosters and stingers. Anything above this weight risks damage to roads, bridges, cargos and the safety of the motoring public. To haul freight exceeding 20,000 pounds, an additional axle — with appropriate spacing (which can vary by state) — will need to be utilized. Tandem-axle trailers, where each axle is spaced no less than 45 inches and no more than 96 inches apart, can legally haul 34,000 pounds on two axles. Coupled with its semi-tractor’s two drive axles, standard tandem-axle trailers (such as step-decks and flatbeds) can get up to 48,000 pounds of weight without needing to permit. That said, every state sets different boundaries for the tandem-axle loads that exceed these thresholds. As a general rule of thumb — when looking to transport overweight, single piece, freight through the majority of states — you should be able to get anywhere from 22,000-25,000 pounds per axle on your tandem-axle trailer through permitting. Although it’s important that you consult an experienced transportation provider before moving overweight freight, you can expect to be allowed 22,000 pounds per axle (44,000 total) for these loads in the majority of states. For your reference, here are the legal total cargo-weight thresholds for tandem-axle trailers across the United States and Canada:. When you have a single piece of freight to move, it’s possible to exceed a gross vehicle weight of 80,000 pounds — with the right due diligence and proper permitting. The total amount of weight you can carry on your tandem-axle trailer will depend, primarily, on which state(s) your load needs to traverse and the construction of the equipment used to do so. Once you’ve selected your route and have acquainted yourself with the tandem axle weight limitations of each state you’ll interact with, this problem becomes easier to solve. For example, let’s say you need to move freight through North and South Dakota. Both of these northern states allow 44,000 pounds on tandem-axle trailers. Coupled with the 34,000 pounds offered by the drive axles and the 12,000-15,000 offered by the steer axle on the semi-truck hauling your load, you could haul up to 93,000 pounds of gross vehicle weight on this shipment with proper permitting. It should be noted that although the weight of your load doesn’t need to be evenly distributed, the weight placed on each axle grouping cannot exceed legal limits.
Comments are closed.